Accesing Microsoft SQL Server Linked Servers

What are Microsoft SQL Server Linked Servers?

“Linked Server” is a feature of MS SQL Server that allows access to non-SQL Server databases through SQL Server. Only SQL Server Developer and SQL Server Enterprise versions support Linked Servers. SQL Server Express edition has several limitations that do not allow configuring or using Linked Servers.

A Linked Server enables the SQL Server Database Engine to execute commands against OLE DB data sources outside of the instance of SQL Server. Many types of OLE DB data sources can be configured as linked servers such as  Microsoft Access, Excel, another instance of SQL Server, etc.

Linked servers offer the following advantages:

1. Remote server access.
2. The ability to issue distributed queries, updates, commands, and transactions on heterogeneous data sources across the enterprise.
3. The ability to address diverse data sources similarly.

A linked server definition specifies the following objects:

• An OLE DB provider: DLL that manages and interacts with a specific data source

• An OLE DB data source: Identifies the specific database that can be accessed through OLE DB (although data sources queried through linked server definitions are ordinarily databases, OLE DB providers exist for a variety of files and file formats.)

How to configure a SQL Server Linked Server to connect to Denodo?

Virtual DataPort provides access to ODBC clients through the PostgreSQL ODBC driver. To install the driver, follow the steps of the Virtual DataPort Developer Guide Section “Access through ODBC”.

Once the DSN to a Denodo database  is created on the system, a Linked Server to Denodo can be configured.

1. Create a User DSN to a Server name (Server1)

2. Start the SQL Server Management Studio and under Object Browser expand Server Objects and right click Linked Servers as shown below:

3. Click on New Linked Server. On the new window fill in the information as shown to create linked server under the General tab.

4. On the Security tab, select the  ‘Be made using this security context’ option and enter the credentials to the Denodo Server.
5.  Remote Login : SQL Server login user name : sa 
6. Password : Sql Server Password : 123 

5. Finally, under the Server Options tab, change RPC, RPC Out, and Lazy Schema Validation options to True (by default they are set to False).

6. Click Ok, after making all the mentioned changes. This will create the linked server and it will be listed under SSMS Object Browser. Right Click on the new linked server and click on Test Connection

How To Install Microsoft Security Essentials In Windows Server 2012 R2

Microsoft Security Essentials Installation Guide For Windows Server

Download and Install

1. Firstly you’ll want to download Microsoft Security Essentials onto your Windows server. Select the language of your choice and either 32-bit or 64-bit depending on the architecture your server operating system is using.
   
2. Save the mseinstall.exe file somewhere locally on the server, do not simply run it as by default the installation will fail with the following error:

   Microsoft Security Essentials cannot be installed on your operating system.
   
   Your version of the Windows operating system is not supported by this program.
   
   Error code:0x8004FF04
   

   
   
3. To get around this error message, right click the mseinstall.exe file and select properties.
   
4. From the properties window, select the compatibility tab. Within the compatibility tab tick “Run this program in compatibility mode for:” under Compatibility Mode and select Windows 7 from the drop down box, as shown.
   Click OK to continue.
5. If you were to run the mseinstall.exe file at this point, you would receive a different error as shown below:

   Microsoft Security Essentials cannot be installed on your operating system. 
   
   Windows Program Compatibility mode is not supported by this program.
   
   Error code:0x8004FF71
   

   
   In order to resolve this, run command prompt as administrator and enter the folder where the mseinstall.exe file is located. Run the mseinstall.exe file with the /disableoslimit flag on the end as shown below. cd C:\Users\Administrator\Downloads
   
   
6. The installation wizard should now correctly open and Microsoft Security Essentials can now be installed and will proceed without the previous error messages, click Next to continue and work through the installation wizard.
   
7. Once the installation has completed you can optionally update and perform a scan, this is recommended as the definitions database needs to be kept up to date to find newer threats. An Internet connection will be required to download any available definition updates through the application, however these can also come through from Windows updates so if you have a WSUS server you can update from here as well. After updating a quick scan will take place.
   You can select the Settings tab to modify when the weekly automatic scheduled scan takes place, by default a quick scan is set to run every Sunday at 2am and will not use more than 50% of the available CPU resources.
   
   

Testing

8. Now that Microsoft Security Essentials has been successfully installed, we will test the actual functionality of the program to ensure that it will correctly identify a threat. To do this we will create a test EICARs file and see if the real-time protection automatically detects and quarantines it. Essentially we are just going to open Notepad and create a .txt file containing the test string defined on that page and then save it to the desktop.
   
   
9. Shortly after saving the file we have been visually alerted that malware has been detected and that Microsoft Security Client is taking action to clean the detected malware.
   If we check the History tab of Microsoft Security Essentials we can then see the test file listed as a quarantined item, confirming that it is working correctly as intended in Windows Server 2012 R2.
   
   

Summary

Although not officially supported, we have successfully installed Microsoft Security Essentials (a cut down Windows Defender) in Windows Server 2012 R2 and confirmed that it is working correctly and detecting security threats.
This is better than the default level of security, which is none as Windows Defender is only built into Windows 8, 8.1 and 10 client operating systems, however it is recommended that server operating systems make use of enterprise solutions such as System Center Endpoint Protection (SCEP) or some other option available from some security vendor.